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Monday, July 27, 2009

I came accross this a few days ago. It looks like an interesting satellite with a linear transponder as well (2m/70cms). Here are some details...

"AMSAT-UK has announced a new amateur satellite project – FUNcube – that features a 435 to 145 MHz Linear Transponder for SSB/CW operation.

FUNcube is an educational single cubesat project with the goal of enthusing and educating young people about radio, space, physics and electronics.

The target audience consists of primary and secondary school pupils and FUNcube will feature a 145 MHz telemetry beacon that will provide a strong signal for the pupils to receive.

It is planned to develop a simple receiver board that can be connected to the USB port of a laptop to display telemetry in an interesting way.

The satellite will contain a materials science experiment, from which the school students can receive telemetry data which they can compare to the results they obtained from similar reference experiments in the classroom.

FUNcube is the first cubesat designed to benefit this group and is expected to be the first UK cubesat to reach space.

It is anticipated FUNcube will be launched into a Sun Synchronous Low Earth Orbit about 600-700km above the earth using one of the many launch opportunities that exist for Cubesat missions. In such an orbit the satellite passes over Europe approximately 3 times in the morning, and 3 in the evening, every day, perhaps allowing the morning passes to be used for educational purposes and the evening passes for Amateur Radio communications.

FUNcube will carry a UHF to VHF linear transponder that will have up to 1 watt and which can be used by Radio Amateurs worldwide for SSB and CW communications.Measuring just 10 * 10 * 10 cm, and with a mass of less than 1kg, it will be the smallest ever satellite to carry a linear transponder and the choice of frequencies will enable Radio Amateurs to use their existing VO-52 or DO-64 station.

A key feature of the satellite is the absence of an On-Board Computer. For reliability and maximum power efficiency, the design has been kept as straight-forward as possible with satellite control being achieved using simple commands. "

Sunday, July 19, 2009

Left the rig on overnight on the 18th/19th of July. One of the ususual signals this time was ZL2FT in New Zealand.

Timestamp Call MHz SNR Drift Grid Pwr Reporter RGrid km az

2009-07-19 06:34 ZL2FT 10.140222 -22 0 RF70mb 5 EI7GL IO51tu 18664 10

2009-07-19 06:26 ZL2FT 10.140223 -22 0 RF70mb 5 EI7GL IO51tu 18664 10

2009-07-19 06:16 ZL2FT 10.140223 -21 0 RF70mb 5 EI7GL IO51tu 18664 10

2009-07-19 06:12 ZL2FT 10.140224 -22 0 RF70mb 5 EI7GL IO51tu 18664 10

Looking at the map on the WSPR website, I was the only European station to hear him that morning. Why??

I assume it was a short-path signal over the artic? If so, my take-off in that direction is excellent with the ground to the north here falling away rapidly. Is that the reason? Is it just because I am in the North-West of Europe? Combination of both?

I'm just suprised that I should be the only one in Europe to hear the ZL station when my horizontal antenna is only 4-5 metres above ground, hardly a 'DX' set-up.

18th July......The summer Sporadic-E season seems to be on the wane a bit with more days on 50 MHz with no openings. The 18th of July was an exception as the band seemed to be open to somewhere most of the day with brief surges in activity.

I worked 20 stations in 15 locator squares over 4 seperate activity periods. Much of the activity seemed to be from Scandanavia and I even managed to pick up 2 new locator squares up there....something that is unusual considering that I have been on 50 MHz for about 18 years ;o)

The most unusual contact was when W3UR in Maryland called me! I had to ask him to repeat his call as I was sure I had made a mistake...but no, it was W3UR in FM19. It's kind of funny to think that W3UR would end up calling someone in Europe on 50 MHz with home made 2 element wire beam in the attic of their house pointing the wrong direction!

It makes me wonder what could I work if I had an antenna for 50 MHz outdoors?? Maybe next year...

Friday, July 17, 2009

The majority of stations using WSPR seem to mainly use 30 metres. In an attempt to encourage more use of other bands, special activity days are organised every week. For this one, I opted to listen on 40 metres and left the rig on receive from early on the 15th to around 08:00 on the 16th.Using my very low doublet antenna (~5m agl), several European stations running around 1 to 5 watts were heard, nothing special. One notable exception was DL6NL who was running only 50 mW and was heard for the whole day, even at local noon which is probably a sign that the MUF was pretty low.

The following DX was logged...

VE3ODZ (5w)

WB4KLJ (2w)

KE7A (5w) in Texas...consistent signal for ~4-5 hours both mornings.

PY8ELO (20w)

VK6POP (10w)...heard several times on the evening of the 15th. First heard 16:00...several hours before local sunset & several hours before sunrise in VK.

KE0CO (5w) & W7RDP (5w) in Washington state in the NW USA.

2009-07-16 04:34 KE0CO 7.040085 -26 0 CN87tl 5 EI7GL IO51tu 7317 kms

2009-07-16 04:56 W7RDP 7.040073 -23 0 CN87xo 5 EI7GL IO51tu 7291

2009-07-16 04:34 W7RDP 7.040073 -22 0 CN87xo 5 EI7GL IO51tu 7291

Both stations (3 spots in total) were only heard at my local sunrise which was at 04:33. I was suprised to see that I was the only station in Europe to hear them that morning!

The following morning I noticed something similiar on 30 metres where only 2 European stations heard AC7SM in Las Vegas, Nebraska running 5 watts. GM4YJB had one spot at 03:30 and these were my spots...

2009-07-17 05:26 AC7SM 10.140218 -27 0 DM26ie 5 EI7GL IO51tu 7937 39

2009-07-17 03:22 AC7SM 10.140219 -27 0 DM26ie 5 EI7GL IO51tu 7937 39

2009-07-17 03:12 AC7SM 10.140219 -30 0 DM26ie 5 EI7GL IO51tu 7937 39

This time, the 'sunrise' effect was not so obvious....perhaps it is more pronounced on the lower bands like 40 & 80m?

I would have thought that other European stations with better antenna systems would have heard these US stations as well? These initial results would suggest that location is just as important. I must check again on another few mornings to see if something similiar happens again.

Sunday, July 12, 2009

I spent the weekend trying out WSPR......'Weak Signal Propogation Reporter'. It's a new type of mode which was only developed in April 2008 and allows users to detect very weak signals with the soundcard on their PC's. I saw this mentioned on the Soldersmoke Blog recently so I downloaded the software.

It basically works as follows.....

1) You tune to a specific frequency on each band. On 30 metres, the most popular band for these kind of signals, you set your rig to 10.138700 MHz on USB.

2) The software listens to the received audio from 1.4 to 1.6 khz. This equates to 10.140100 to 10.140200, a 200 Hz wide section of spectrum.

3) For a basic receive set-up, just put the microphone from your PC next to the loudspeaker of your rig and run the software.

There are a few issues that still need to be resolved. You need to set the time on your PC so that it is accurate to within 1 sec. You also need to find out where 10.138700 MHz is! You can't assume that your rig is accurate. I found that on my rig, I had to set it to 10.138778 MHz.

The main website for WSPR reports is WSPR Net which lists all the WSPR spots and can also display them on a map.

The picture above is a screenshot of the WSPR screen. The horizontal waterfall displayat the top shows the signals heard in the 200 Hz band split up into 1 minute segments. In the data section below it, the 2nd column is how far below the noise floor the signal is. The last 3 columns on the right are callsigns heard, their locator square and their power in dBm (20 dBm=0.1 watts, 27dBm=0.5w, 30dBm=1w, 33dBm=2w, 37dBm=5w, 40dBm=10w).

Most stations seem to be running around 1 to 5 watts and over the space of a day, I was hearing signals from both sides of the Atlantic. The activity level seems a little low so perhaps it is still a mode that is only growing? Still, I was suprised at what was heard with the WSPR software digging out signals buried in the noise. Here is a map of what was heard in 30 minutes on a Sunday afternoon in July. Note that the antenna in use was a low doublet antenna only about 4-5 metres above ground level.

As a mode, WSPR has a lot of potential. Some of the advantages might be....

1) You can automatically see if various propogation paths are open although a lack of global receiving stations might make this difficult?

2) Within minutes of sending out a signal, you can see what type of signal you have at various receiving stations.

3) By using very low power, you should be able to see roughly how you are getting out. Then if you make any major antenna changes, you should be able to get instant feedback on your signal strenght?

For anyone interested in very low power operation, this mode has obvious attractions. I tried messing about with QRSS (slow speed CW.....a dot = 3 seconds!) and I found it difficult to find let alone read the signals. WSPR seems to have a lot more potential.

Friday, July 10, 2009

There was a nice opening on 50 MHz into Europe on the 6th of July. I worked 29 stations in 23 grid/locator squares. It's only when I plotted out the various squares that I noticed the usual oval shaped footprint which is pretty common with Sporadic-E. Most contacts were in the 1200 to 2000 km range.

Two contacts stood out....

1) YO7LCB in KN15OA at 2428 kms. Almost certainly not single hop. Probably double hop or chordal hop Sporadic-E.

2) UT5PI in KN77OM at 3123 kms. Double hop.

Working double hop on 50 MHz is pretty common but it's still nice to do it, especially with an indoor 2 element beam in the attic made from scrap pieces of TV coax ;o)